Blaze Medical Devices (Blaze) is dedicated to improving the safety and the efficacy of the nation's blood supply. Blaze is developing a test to quantify the prospective efficacy of each Red Blood Cell (RBC) unit. The need for such testing is predicated upon the adverse effects and unpredictable efficacy of transfused RBC due to inter-donor variability, differences in manufacturing methods and prolonged RBC storage. Significant data show that these differences can cause ambiguities about the quality of individual RBC units that time alone cannot adequately reflect. For 15 million units of pRBC transfused annually in the US, the cost of suboptimal efficacy by itself has been estimated at about $17 billion. RBC mechanical fragility (MF) reflects an array of biochemical and biomechanical changes during storage, and tracks the loss of plasticity that red blood cells need to survive in vivo and to deliver oxygen effectively. MF had been proposed as an in-vitro metric potentially predictive of transfusion outcomes. However, the clinical relevance of such a metric still remains to be demonstrated. The hypothesis of the Phase I research is that RBC MF can be used as an aggregate parameter predictive of RBC survival post-transfusion, and that this is at least partially time-independent. In this project Blaze's Phase I Specific Aim 1 is to establish the reliability of RBC mechanical fragility as a metric of post-transfusion performance measured through incremental patient hematocrit and total hemoglobin (primary outcomes); and Specific Aim 2 is: to establish the reliability of RBC mechanical fragility as a metric of post-transfusion performance measured through in vivo hemolysis markers of plasma Hb, bilirubin, haptoglobin and LDH (secondary outcomes). Phase II research will further validate the RBC in vitro MF as a metric to predict transfusion outcomes, and optimize the test for clinical use. Blaze will provide base devices and consumables for RBC mechanical fragility testing. The innovation of Blaze's product can solve the longstanding problem of MF testing being difficult to standardize for wide acceptability - by offering a rapid and reliable test that requires very little sample to generate data- rich multi-dimensional fragility profiles, by utilizing its patented optical and processing techniques. The long-term goal of the project is to improve the efficacy and safety of blood transfusions through quantifying - and potentially predicting - the changes in RBC viability during storage. As a first commercial application, Blaze' test will enable more efficient management of Hospital Blood Bank inventories - for example, by switching from the current FIFO (First-In-First-Out) to a SRSL (Shortest Remaining Shelf Life) approach. Follow-up applications can be potentially expanded to provide for selection and/or screening of donors with non-storable blood, assessing a given unit's suitability for a particular clinical use (e.g. g-irradiation), or suitability for particular patient groups (e.g. neonatal, trauma, chronic anemia).